Former Firefox Developer: Remove Your Antivirus Software

Robert O’Callahan, a former Mozilla employee, recommended in a blog post that you remove antivirus software and only use Windows Defender. According to him, the programs do more harm than good.

O’Callahan claims that evidence that third-party antivirus software improves a computer’s security is negligible. Any differences in detection rates are negated by leaks in the antivirus software itself and by, for example, overloading users with annoying notifications, teaching themselves to ignore the warnings of the protections.

The former Firefox developer further expresses frustration at how antivirus programs can create various barriers to browser development. For example, developers may want to make certain changes to the browser that improve security, while poorly written antivirus software prevents this. He cites an example where attempts to enter aslr were prevented by conflicts with anti-virus software. Furthermore, there would be a lot of development time involved in bypassing problems created by antivirus software, which could otherwise also be spent improving the browser’s security.

Another problem that O’Callahan points out is that software developers have to follow a narrow path to keep both users and antivirus companies happy. Recommending a user not to use certain antivirus software is generally not to the liking of both the user and the company behind the software. Therefore, it is difficult to expose the mentioned problems without getting into trouble with other instances. In addition, users attribute problems caused by antivirus programs to the browsers rather than the antivirus software.

Incidentally, he emphasizes that his argument only applies when the user is running an updated version of his operating system. When using Windows 7 or even XP, he does recommend using antivirus software “to be just a little less doomed.”

O’Callahan spent 16 years at Mozilla, where he made major contributions to Firefox. He stopped there in March 2016 because he said he was getting tired of it and wanted to spend more time developing rr, a debug program. Now that he is no longer affiliated with Mozilla, he says he has the freedom to write this message.